Maintaining the structural integrity of certain structures is very important in many fields because of safety concerns, downtime, cost, etc. Loss of structural integrity is typically caused by material defects, such as cracks, disbonds, corrosion, voids, etc. that may exist in or on the structure. For example, it is important in the power generation industry that reliable techniques are available to examine the structural integrity of turbine engine, generator and other plant equipment to ensure the components and systems do not suffer failure during operation. In particular, the structural integrity of turbine blades and rotors requires monitoring through inspections to facilitate the long term service life of the turbine engine. A common method for detection of a crack or defect is visual examination by skilled personnel. However, it is known that cracks or defects that may affect the integrity of structural components may not be readily visible without the use of special techniques to aid the examiner. Therefore, various techniques have been developed in the art for non-invasive and non-destructive analysis of different structural components and materials in various industries.